1. Field of the Invention
The present invention generally relates to diode lasers and more specifically, to end pump configurations and techniques for diode array end pumped slab lasers.
2. Description of Prior Art
Current lasers used in rangefinders are either low repetition rate or too expensive for many applications. Diode pumped solid lasers lead to more efficient operation and therefore can be smaller and lightweight, but often do not operate over environmental temperature ranges without inefficient and cumbersome temperature control. Military lasers are required to be low cost, compact, and operate over a wide temperature range. Previously designed diode pumped solid state lasers have used transverse pumping techniques which are effective, but require temperature control and are less efficient than desired. Previous end pumped lasers used cylindrical rods and thus did not have efficient mode/pump overlap. Previously used flashlamp pumped solid state lasers are limited in repetition rate due to excessive heating and in addition have a shorter operating time before replacement of the flashlamp pumps. There is a need for smaller, more efficient, lower cost lasers which are capable of moderate repetition rate operation for military applications such as laser rangefinders and target illuminators.
While the prior art has reported using solid state end pumped lasers none have established a basis for a specific apparatus and technique that is dedicated to the task of resolving the particular problem at hand. What is needed in this instance is a new apparatus and technique that insures that most of the pump light will be absorbed and coupled into the laser mode even if the absorption coefficient is low resulting in a laser that will operate efficiently over a wide temperature range even as the laser diode pump wavelength varies.